New technology could reduce the amount of energy for air conditioning

In much of the world, AC power demand peaks later in the day when solar power supply is minimal or zero. So pairing as you suggest would require a huge amount of storage capacity. Or in some places they could also use high voltage transmission lines to areas further to the west that are still receiving significant sunlight at that time.

Energy is only free at times when we don't actually need it.

Rayhem• 2 years ago

A/C is interesting because it has something of a built-in capacity system. "Super" cool the building during times of the day when power is readily available, and that cooling then persists. You don't have to store the electrical power specifically.

vundercind• 2 years ago

And where are those?

Installed cost, I mean. Assume, like in most houses, none of the supporting electrical work has been done for solar already.

Where’s the dirt cheap home solar?

elric4• 2 years ago

It's wasteful, and that "free" energy could be used for more productive purposes.

carapace• 2 years ago

The second law of thermodynamics would like a word...

tantalor• 2 years ago

Last episode of Tech Ingredients teased this:

https://youtu.be/hc_HcT4pIOE?si=0Nn1HwY-rpvhny9H&t=922

  in the next video we're going to
  show you how to improve the efficiency
  of air conditioners and not by a small
  amount it's estimated that approximately
  $200 billion a year is used worldwide to
  generate the electricity that drives air
  conditioning so even a few per reduction
  in the cost of running an air
  conditioner would make a huge difference
  and could save billions of dollars and
  what we're going to show you isn't going
  to improve the efficiency by a small
  amount but by a huge amount so stay tuned

netcraft2• 2 years ago

I was talking with someone from Greece recently who was experiencing a heat wave and they dont have AC. I am from the south eastern US where we are basically required to have AC for de-humidification as much as cooling - we would be overrun with mold and mildew without AC in the summer. Our heat indexes regularly reach 105F during the summer and sometimes much higher. I joked the other day that if our aquifers ever ran out of water we could probably get most of what we need with just a better dehumidifier.

Edit to add: just in case, you should never use water out of a dehumidifier for anything but grey water use cases unless you sanitize and purify it - it can make you very sick!

jvanderbot• 2 years ago

That's not really a joke. Even in Minnesota summers, I pull 2 gallons every couple days out of our basement air. That's enough for me. I've given serious thought to putting a couple outside to capture water for our sprinkler system / gardening irrigation, if it weren't for this year's 100 year rains.

ghaff• 2 years ago

Yeah, in New England I really need a dehumidifier in the basement. It's a bit damp in any case (old fieldstone) but the dehumidifier keeps it from getting really bad.

amykhar• 2 years ago

It would be cool if they could put some of this technology into commercial grade dehumidifiers even before they get put into HVAC systems. If you could run a super efficient portable dehumidifier and boost the performance of your HVAC system, it would be much faster to reduce overall energy consumption because it would be far less expensive than upgrading an entire HVAC system.

vel0city• 2 years ago

Most portable electronic dehumidifiers are just small AC units with the hot and cold side in the same room.

sumtechguy• 2 years ago

My area is currently in drought. My yard is basically dead/hibernating. Except around the waste water outlet from my heat pump. That is nice and green.

nojvek• 2 years ago

The irony is that in high humid climates, as the sun goes down and night gets cooler, that gets the humid air cool enough to turn into rain.

So Florida is known as the sunshine state, but it's also the rainy state. It rains 2.5x more by inches than it does in Rainy Seattle.

bschwindHN• 2 years ago

Sorry to comment on the site and not the article, but goddamn. I have an old phone and visiting news sites like wired make it as hot as if I'm playing a video game, and the page had to reload several times like it ran out of memory. I lost 15% of my battery in 2 minutes of reading.

Wired (and other news sites), what the hell are you doing to computers? Stop it. People on newer phones may not notice it, but they're still burning just as many cycles on whatever stupid bullshit you decided to add to your site.

Maybe we wouldn't need so many air conditioners if sites like yours didn't exist.

explaininjs2• 2 years ago

This makes me want an LLM that traces every line of code running on a site and provides a summary…

“when you scrolled the page 2 pixels just now, it triggered 500 network requests to various tracking sites. additionally, it forced redrawing the site 3 times, and consumed 400ms of GPU time.”

ohthatsnotright• 2 years ago

Why on earth would you involve a larger waste of resources to summarize something which is capturable and displayable without?

tijtij• 2 years ago

I have newerish phone and I still run Kiwi Browser with the uBlock Origin extension for this very reason.

skybrian2• 2 years ago

This is a case where the archive link really helps. See: https://archive.is/IXVvu

kjkjadksj2• 2 years ago

The mobile web is shit like this now. I avoid it like the plague and just wait until I can get in front of a desktop os with proper ad blocking.

HPsquared2• 2 years ago

Advertising nudge from phone makers? "My phone is too slow to browse the web, I need a new one". Especially on a "tech magazine" like Wired, the ultimate purpose is to advertise tech.

lsaferite4• 2 years ago

I think they alluded to it in the article, but when a heat pump is cooling the inside it's generating lots of heat on the outside. They could/should/likely are using that 'waste' heat to dry out the desiccant. Seems like a great plan.

I often wonder why hot water systems aren't linked into the HVAC as well. I know you can get heat pump water heaters, but it seems like integrating it into the HVAC system would potentially allow for system scale optimizations. I would assume the cost/complexity is too much for residential systems. For that matter, refrigeration in homes falls into the same category as they are a heat pump that's dumping waste heat into your living space.

robnado• 2 years ago

Combining refrigerator, water heater and heat pump implies the need for transferring the fluid used as refrigerant between these components. This is usually a gas that is not trivial to contain, so creating this shared pipeline increases the points of failure. Further, you now have to insulate the entire length of this system, using material to do so, and you will end up losing a certain amount of efficiency anyways in this piping system. Also, what if your need in hot water is much greater than your need to cool the house or vice versa, what is your backup system for disposing of heat or cold when not required? It’s not certain that after solving all these problems and others, that you still have a net efficiency gain.

alanbernstein• 2 years ago

I like to imagine a world where it's acceptable for houses to be designed around a utility room where all of these interchanges, insulation, isolation, exhaust, issues can be contained, and accessed, in a small, separate, space that is not part of the living area.

nanomonkey• 2 years ago

I think you could get away with two insulated reservoirs (frozen and hot water) and then use something like glycol, alcohol or water to shuttle hot and cold to your shower, under floor heating/cooling. Frozen water can be mechanically stirred (like a slushy machine) to keep it from freezing solid, allowing you to pump it through pipes. Water can also be mixed with salts or alcohol to alter it's freezing temperatures, with allow you to move cold from your freezer to the refrigerated areas (fridge, computers or living spaces). You can also use air as a working fluid. Any excess can be dumped to the outside environment with a radiator as a last resort.

Modern cars are already doing this with heat pumps to manage batteries and the cabin temperatures.

It's pretty easy to see where building technologies will go by looking at car technologies...

nicpottier• 2 years ago

These do exist but are indeed complicated. Still pretty new. Usually used with hydronic systems.

skybrian2• 2 years ago

Apparently integrating appliances that use refrigerant piping isn’t so easy, compared to self-contained units that just need electricity. It looks like mini-split systems require professional installation.

I wonder if there is another way to connect things?

lazide2• 2 years ago

Refrigerant lines tend to be high pressure (300+ PSI) and the system as a whole is intolerant of leaks - even tiny pinhole leaks - over time.

netcraft2• 2 years ago

there are many mini-split heat pump systems that can be installed by a homeowner without a professional installation now. An example: https://www.youtube.com/watch?v=ZmwZVD2KEDY

sandworm101• 2 years ago

If this were a continuous commercial operation then heat from one process would definitely be used in another. That does save money. The problem is that residential use will be variable and intermittent, requiring a host of sensors and valves to turn loops on and off depending on random needs. And when say one process needs to dump heat, but that heat isn't needed elsewhere (ie the hot water tank is already hot) then equivalent backup radiators must on standby to take the load. That is all just too much control circuitry for residential devices normally controlled by just one bang-bang (on/off) control.

cool_dude852• 2 years ago

Where I live, few installers have specialized in heat pump water heaters, and it's still seen as a niche technology. This means the cost increase compared to a standard electric or gas water heater is high and installation issues are common. You also run into a lot of situations where the water heater is placed in conditioned space which makes any energy savings a lot more sketchy.

Adding different systems to the mix, to where we now need the HVAC guy, plumber, etc. to all set up a working system together seems like a recipe for disaster.

smileysteve• 2 years ago

You also run into a lot of situations where the water heater is placed in conditioned space which makes any energy savings a lot more sketchy.

Assuming these were the prior positions of a non heat pump system, you've gone from creating heat to transferring heat; while both radiate heat, the heat pump is much closer to net 0.

elric4• 2 years ago

Heat pump systems in combination with underfloor heating are sort of common in new homes over here (not the norm, but common enough). The heatpump heats the floor in winter, cools it in summer. The heat is stored in a large water tank, and it can be transferred to potable water for showers and whatnot.

Best part is, you can supply heat to the tank in multiple ways, even concurrently. Think heat pumps, solar water heaters, or even a fireplace if you're so inclined.

ianburrell• 2 years ago

I have seen water heat pump systems. They are meant to replace boilers for radiators or under floor heating. Then the hot water can be stored. Or go to a heat exchanger for heating and cooling with ducts. Water is much easier fluid to work with than refrigerant.

One reason don't see combined systems is that refrigerator and water heater don't move that much heat. Refrigerator is fine dumping the heat into the kitchen, and water heater pulling heat from the basement. The air inside the house turns into the working fluid.

T3OU-7362• 2 years ago

Another trend I have seen[1] ] (US market, high performance/high energy efficiency homes) is the use of HVAC and separate, standalone dehumidifier to do the same thing - take out humidity out of the air that the AC system has to otherwise both cool and dehumidify on it own.

The framing (at least as I understood it) was more on the psychometric side - 24C@65% relatuve humidity _feels_ worse than 27C@45%RH, but the energy savings aspect is also non-trivial.

As an aside - a fairly large number of central AC systems in the US do not have a humidity censor, so they only go by the temperature set point. Upgrading to control system which does measure humidity, while energy inefficient (because AC would be used to dehumidify the air _below_ the target set point), is an option, though not as good as having a stand-alone humidity control system. Sadly, I am unaware of Nest and/or Ecobee's support for this sort of a setup. Probably not cost effective for them. :\

[1] https://youtu.be/rWWLW4nLNBI?si=Ud1jk3x58H6pnMci

bob1029• 2 years ago

Another option is a variable speed condensing unit. This is what I am looking at doing next.

A dedicated central dehumidifier is nice, but I've found them to be kind of noisy, especially when installed in the attic. Its got its own compressor, so the vibrations will transfer into the structure.

kjkjadksj2• 2 years ago

Part of this is solved by sizing the ac correctly. Too powerful an ac and it doesn’t cycle as often and humidity builds.

hunter2_• 2 years ago

Sadly, I am unaware of Nest and/or Ecobee's support for this sort of a setup.

Same, and the worst part is that Nest already includes a hygrometer to show humidity in the app. All they need to give the user is a toggle: setpoint in regular dry bulb temperature, or setpoint in calculated wet bulb temperature (or heat index or "feels like" or whatever user-friendly calculation). Although their remote temperature sensors don't have a hygrometer, only the main unit.

wongarsu• 2 years ago

The framing (at least as I understood it) was more on the psychometric side - 24C@65% relatuve humidity _feels_ worse than 27C@45%RH

It's complicated to quantify, but in a sense 24C@65% is warmer than 27C@45%RH. Or rather, maintaining your body temperature is more difficult in the former than in the latter.

The human body produces ~100W of heat, and the primary way to get rid of it in warm weather is evaporative cooling: at below 100% relative humidity water slowly evaporates, this takes energy and thus cools down the surface the water was sitting on. We use that by coating us in sweat and letting it evaporate. This is more efficient the lower the relative humidity is.

The attempt to quantify this in a nice metric is the wet bulb temperature (what would a thermometer with a wet cloth around it show). 24C@65% is a wet bulb temp of 19.3C, 27C@45% is a wet bulb temp of 18.8C

toast0• 2 years ago

Sadly, I am unaware of Nest and/or Ecobee's support for this sort of a setup. Probably not cost effective for them. :\

I've got both of these. Nest has a setting for 'cool to dry', but my climate is usually not humid and hot at the same time. I don't see a similar feature on the Ecobee, but the Ecobee app is perhaps more confusing. It does send alerts when the detected humidity is above set points. Where I do have issues with humidity is in my basement; typically the basement stays around 5-10 F less than the first floor, and if the first floor is 50% relative humidity, moving the air into the basement results in a much higher relative humidity. If the a/c is running for the first floor, there's a good chance of significant condensation on the vents right after the air handler.

johntb86• 2 years ago

Sadly, I am unaware of Nest and/or Ecobee's support for this sort of a setup. Probably not cost effective for them.

Ecobee has a setting to enable this: https://support.ecobee.com/s/articles/How-to-use-AC-Overcool...

They also have a setting to adjust the temperature for humidity: https://support.ecobee.com/s/articles/Adjust-the-Temperature...

T3OU-7362• 2 years ago

Right, I wasn't specofic - Ecobee will overcool with the main AC, but it does not have the 'I have a dehumidifier in my HVAC setup, go use THAT' setting.

habitue• 2 years ago

Since this article uses that fluffy "tell a story" writing style, here's the facts in the article stripped out:

1. Air conditioning consumes 10% of global energy and 20% of energy used in buildings.

2. Demand for cooling is expected to increase significantly, with 2/3 of world households projected to have air conditioning by 2050.

3. Dehumidification accounts for over half of energy consumption in air conditioners in humid conditions.

4. New technologies are being developed to improve air conditioning efficiency:

   a. AirJoule by Montana Technologies:
      - Uses metal-organic framework material for dehumidification
      - Claims to reduce energy for dehumidification by up to 90%
      - Still in prototype and testing stages

   b. Blue Frontier:
      - Uses liquid desiccant for dehumidification
      - Being installed in various locations in the US

   c. IceBrick by Nostromo Energy:
      - Energy storage system for large-scale cooling
      - Can reduce annual cooling costs by 30% and associated emissions by up to 80%
      - Only suitable for centralized cooling systems

   d. Gradient:
      - Window-based heat pumps with larger external units for better efficiency
      - Currently costs $3,800, aiming to reduce to $1,000

5. Electrocaloric cooling is being researched as a potential future technology, potentially 20% more efficient than current methods.

6. Passive cooling measures (e.g., window shutters) should not be overlooked as they cost nothing to run.

7. Current non-centralized air conditioners operate at only about 20% of their theoretical maximum efficiency.

klabb3• 2 years ago

6. Passive cooling measures (e.g., window shutters) should not be overlooked as they cost nothing to run.

What about insulation? In my experience the insulation in most hot places is abysmal, compared to cold places. I’m not even a layman, but shouldn’t the physics work the same? Or does the air flow from AC change the equation?

cool_dude852• 2 years ago

I live in Florida and new-build homes are relatively well-insulated. Older stuff can be anywhere from very poor to surprisingly good (e.g. old, small concrete block housing). And yes, the idea is broadly the same, although insulation doesn't help with de-humidification.

danans• 2 years ago

What about insulation? I’m not even a layman, but shouldn’t the physics work the same? Or does the air flow from AC change the equation?

Insulation works great in hot climates, but only when the building is also well air-sealed and air-conditioned. Otherwise, insulation alone will just make a house work like an oven after it heats up (through radiant and convective heat gain).

elric4• 2 years ago

Passive cooling measures (e.g., window shutters) should not be overlooked as they cost nothing to run.

Technology Connections just did a video on awnings. I'm not quite as puppy eyed about them as TC, but they are pretty darn effective.

https://www.youtube.com/watch?v=uhbDfi7Ee7k

bitmasher9• 2 years ago

I hope someone takes the idea from this video and compiles it into more solid and actionable data. I would like something where I can describe my window location and the type of window and it tells me how much cooling I would gain with an awning.

Flimm• 2 years ago

Thank you for the summary! (Note: indenting text with two spaces makes it render with a monospaced font on Hacker News, see https://news.ycombinator.com/formatdoc )

gilleain• 2 years ago

Uses metal-organic framework material for dehumidification

MOFs are super interesting!

https://en.wikipedia.org/wiki/Metal%E2%80%93organic_framewor...

they are one of the most complex non-biological structures I know of

hgomersall2• 2 years ago

In areas where water is not in particularly short supply, you can cool by evaporating water into the exhaust pre-heat-exchanger of an MVHR system. This then vents the warmer humid air into the outside and cools incoming air. The enthalpy diagram suggest it's quite helpful and there's a product on the market that uses exactly this approach.

It's basically half of a closed cycle heat pump, in which the hot side is an externality.

HPsquared2• 2 years ago

Could that increase the humidity in the surrounding street environment?

lsaferite4• 2 years ago

Sounds similar to a swamp cooler.

hgomersall2• 2 years ago

Indeed, but the difference is the high humidity cooled air is used to cool low humidity air, so you don't get the humidity increase inside.

0xbadcafebee• 2 years ago

We could reduce demand for air conditioning if we designed our lives around the natural environment rather than isolating ourselves from it.

Right now we build giant boxes to live/move around in that suck up the sun's heat, then we insulate the box, then build another box to remove moisture in the box, cool the air in the box, blow it around, and then we have to power it...

....or we could live and move around in an open, shaded area, where wind can pass easily, fans blow on us to cool us (your skin is designed for cooling with wind, unlike most other animals on the planet), and cool mists can assist.

The latter is how I stay comfortable while camping in 90% humidity and 90F temperature. There are other solutions too, like staying underground during the peak of the heat, taking a dip in a pool of water, drinking cold liquids. All these and more don't require an exponential increase in energy generation, advanced engineering, or boxes designed to create an artificial environment.

JumpCrisscross• 2 years ago

The system wouldn’t suit a single house, as it only works with these large centralized cooling installations. However, it can be bolted to a variety of chiller plants—it doesn’t really matter what circulating fluid they use, for example, Ben Nun says

We have district heating in New York [1]. Fascinating to think of district cooling, too.

[1] https://en.wikipedia.org/wiki/District_heating

kasey_junk• 2 years ago

Chicago has district cooling https://wgntv.com/news/chicago-news/the-ice-machine-that-chi...

ninininino• 2 years ago

Air conditioning should be applied only the to a bubble of cubic space surrounding the people in a given room as well as any temperature-sensitive goods like medicines, perishables, etc. We ought to develop tech to facilitate this, for example a mosquito net style insulating cocoon to enclose your bed at night that conditions the air inside of it but leaves the rest of the room warm.

kkfx• 2 years ago

Honestly it could be hardly used in practice. The frontier of cooling is:

- living in MODERN, so air-tight, well insulated buildings, designed to get the Sun when needed in winter, but not get it in summer with simple design choices etc;

-living in places where nights are fresh and having p.v. to cool with no energy consumption from grid during the day.

Now the above points are a bit bold but try reasoning why we live where we live. In the past places where circadian thermal delta was/is lower was very good places because it was less hot than now and there was no cheap heating. Similarly living in some places very deep in a valley was nice because floods was a thing anyway, but having clean water was invaluable and homes back then have had much less things who can be damaged by floods. Climate have change but technology, human living is changed much more. In the present world many inhabited parts of the world that back than was nice places, today they are not and others back than not so nice today are nice places.

In the past being many in a single places means:

- being able to defend against enemies

- having access to all professions and services

- having trade and learning opportunities

- be more exposed to illness, BUT being able to get help much easier

now? It means that

- 9/11 alike attacks or simple drone attacks are much more easy and deadly

- you get more dysfunctional services because we are too dense for them in too many place (as an example packages delivery in large condo complex vs single family homes)

- be more exposed to illness, with sometimes even LESS chances of a quick aid

- being mostly limited by nearby activities instead of having plenty of space for build a new one and remote work

Try to weight this, in terms of opportunities, disasters and who win vs who loose.

New technology could reduce the amount of energy for air conditioning

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